1. Department of Chemistry, University of Sheffield, Dainton Building, Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
2. Ashland Specialty Ingredients, 1005 US 202/206, Bridgewater, New Jersey 08807, United States
3. Ashland Specialty Ingredients, Listers Mills, Heaton Road, Bradford, West Yorkshire BD9 4SH, U.K.